Did you know that Earth is approximately 4.54 billion years old? Scientists have determined its age through various sources, including rocks on our planet and those from the moon! According to Mark Popinchalk, an astronomer at the American Museum of Natural History and New York University, early solar systems can be thought of like a pizza - with the star forming from 99% of the "dough" and the remaining 1% flattening out into planets. The formation of our planet involved collisions, spinning, and layering to create its core, mantle, and crust. Life emerged soon after the oceans formed, with cellular life existing uninterrupted for about 3.5 billion years.

Source: https://www.livescience.com/space/planets/how-old-is-planet-earth